Sending mail not working and showing an exception

Question

My program is below:

/* * To change this template, choose Tools | Templates * and open the template in the editor. */ /** * * @author Cygnet */ import java.util.Properties; import javax.mail.Message; import javax.mail.MessagingException; import javax.mail.Session; import javax.mail.Transport; import javax.mail.Message.RecipientType; import javax.mail.internet.AddressException; import javax.mail.internet.InternetAddress; import javax.mail.internet.MimeMessage; public class SendMail { private String from; private String to; private String subject; private String text; public SendMail(String from, String to, String subject, String text){ this.from = from; this.to = to; this.subject = subject; this.text = text; System.out.println("your massege running here"); } public void send(){ Properties props = new Properties(); props.put("mail.smtp.host", "smtp.cygnet3.com"); props.put("mail.smtp.port", "8383"); Session mailSession = Session.getDefaultInstance(props); Message simpleMessage = new MimeMessage(mailSession); InternetAddress fromAddress = null; InternetAddress toAddress = null; try { fromAddress = new InternetAddress(from); toAddress = new InternetAddress(to); } catch (AddressException e) { // TODO Auto-generated catch block e.printStackTrace(); } try { simpleMessage.setFrom(fromAddress); simpleMessage.setRecipient(RecipientType.TO, toAddress); simpleMessage.setSubject(subject); simpleMessage.setText(text); Transport.send(simpleMessage); } catch (MessagingException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static void main(String[] args) { String from = " [e-mail] "; String to = " [e-mail] "; String subject = "Hi server problem"; String message = "I could not find anything in the coding"; SendMail sendMail = new SendMail(from, to, subject, message); sendMail.send(); System.out.println("Your massege is successfully sent"); } } 

I get the following exception:

 run-main: your massege running here javax.mail.MessagingException: Exception reading response; nested exception is: java.net.SocketException: Connection reset at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:1462) at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1260) at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:370) at javax.mail.Service.connect(Service.java:275) at javax.mail.Service.connect(Service.java:156) at javax.mail.Service.connect(Service.java:105) at javax.mail.Transport.send0(Transport.java:168) at javax.mail.Transport.send(Transport.java:98) at SendMail.send(SendMail.java:58) Your massege is successfully sent at SendMail.main(SendMail.java:71) Caused by: java.net.SocketException: Connection reset at java.net.SocketInputStream.read(SocketInputStream.java:168) at com.sun.mail.util.TraceInputStream.read(TraceInputStream.java:97) at java.io.BufferedInputStream.fill(BufferedInputStream.java:218) at java.io.BufferedInputStream.read(BufferedInputStream.java:237) at com.sun.mail.util.LineInputStream.readLine(LineInputStream.java:75) at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:1440) ... 9 more BUILD SUCCESSFUL (total time: 2 minutes 15 seconds) 

Please help me, what mistake am I making? I do not want to authenticate my username and password, my port number and user ID are working fine.

Answer 1

“Connection reset” means something that unexpectedly closed the connection you tried to establish. Your SMTP server might be expecting a secure connection (SSL or TLS). You can try connecting to smtp.cygnet3.com:8383 using telnet or netcat and see what you get. If you have openssl, you can check if it has a secure port with something like openssl s_client -connect smtp.cygnet3.com:8383 .

Edit: As Brian points out, port 8383 is an HTTP server. This is similar to the mail server web interface. Try using the standard port 25 (insecure) or 587 (secure).

Answer 2

There is no SMTP server on this host on this port. You need a valid SMTP server.

A web server running on this port will appear:

 broach@roach-VirtualBox :~$ telnet smtp.cygnet3.com 8383 Trying 66.7.149.27... Connected to cygnet3.com. Escape character is '^]'. HELO? HTTP/1.1 400 Bad Request Content-Type: text/html; charset=us-ascii Server: Microsoft-HTTPAPI/2.0 Date: Mon, 05 Sep 2011 05:35:35 GMT Connection: close Content-Length: 326 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN""http://www.w3.org/TR/html4/strict.dtd"> <HTML><HEAD><TITLE>Bad Request</TITLE> <META HTTP-EQUIV="Content-Type" Content="text/html; charset=us-ascii"></HEAD> <BODY><h2>Bad Request - Invalid Verb</h2> <hr><p>HTTP Error 400. The request verb is invalid.</p> </BODY></HTML> Connection closed by foreign host.